1. Field of the Invention
Embodiments of the invention relate to an image display device and a method for driving the same capable of implementing a two-dimensional plane image (hereinafter referred to as ‘2D image’) and a three-dimensional stereoscopic image (hereinafter referred to as ‘3D image’).
2. Discussion of the Related Art
An image display device capable of selectively implementing a 2D image and a 3D image has been recently raised due to the development of various video contents. The image display device implements the 3D image using a stereoscopic technique or an autostereoscopic technique.
The stereoscopic technique, which uses a parallax image between left and right eyes of a user with a high stereoscopic effect, includes a glasses type method and a non-glasses type method, both of which have been put to practical use. In the glasses type method, the parallax image between the left and right eyes is displayed on a direct-view display or a projector through a change in a polarization direction of the parallax image or in a time-division manner, and a stereoscopic image is implemented using polarization glasses or liquid crystal shutter glasses. In the non-glasses type method, an optical plate such as a parallax barrier for separating an optical axis of the parallax image between the left and right eyes is generally installed in front of or behind a display screen.
There is an image display device, in which a patterned retarder is disposed on a display panel, as an example of the glasses type image display device. The image display device implements the 3D image using polarization characteristics of the patterned retarder and polarization characteristics of the polarization glasses the user wears. Thus, the image display device has a less crosstalk between left and right images of the 3D image and a greater luminance than other stereoscopic image implementation methods. As a result, the image quality of the image display device is excellent.
However, the image display device using the patterned retarder forms black stripes in an area of the patterned retarder corresponding to black matrixes of the display panel as disclosed in Japanese Laid Open Publication No. 2002-185983, so as to widen 3D vertical viewing angle. Therefore, a luminance of the 2D image of the image display device is much less than a luminance of an exclusive 2D display device capable of implementing only a 2D image. The image display device requires light sources, which are more than the number of light sources of the exclusive 2D display device, and a double brightness enhancement film (DBEF), so as to compensate for the luminance of the 2D image. Thus, the manufacturing cost of the image display device increases. As a result, competition of the image display device is reduced.